pngtext 0.1.1

pngtext

A steganography tool to store text or other data inside PNG images.

Getting Started

Follow these instructions to build pngtext

Prerequisites

You need to have these installed on you machine to build pngtext:

1. dub package manager
   
2. a dlang compiler. dmd works
   
3. an internet connection for dub to fetch the dependencies
   
4. git to clone the repository
   

Building

Run these commands to build pngtext:

git clone https://github.com/Nafees10/pngtext
cd pngtext
dub build --build=release

If the build is succesful, the built binary will be in the current directory named pngtext. Copy the binary to a path where the shell can find it (could be /usr/local/bin).

Running Tests

To run the unittests on pngtext, first cd into the directory containing pngtext, and run: dub test

Using

This describes how to use pngtext.

Writing Data to PNG Image

Use the write command to write data or text to a png image.

The following command will read data from stdin and encode it in pngFile.png, and write resulting image to outputPngFile.png: pngtext write -i pngFile.png -o outputPngFile.png [other options]

To write data from a file, use the --file or -f option: pngtext write -i pngFile.png -o outputPngFile.png -f fileContainingData

Reading Data from PNG Image:

To read data, that was written using pngtext, use the read command: pngtext read -i pngFile.png

To read the stored data into a file, use the --output or -o option to specify the output file: pngtext read -i pngFile.png -o outputDataFile

Calculating Maximum Data Capacity from PNG Image:

To calculate exactly how many bytes a png image will be able to store, use the size command: pngtext size -i pngFile.png After asking about the quality of resulting image, it will write the number of bytes pngFile.png can hold if all pixels are used.